ARID1A and mucinous adenocarcinoma of the appendix: Mutations in ARID1A and ARID2 genes are present in appendiceal cancers in general [7], with ARID1A gene mutations reported in appendiceal goblet cell adenocarcinomas [11], appendiceal adenocarcinomas, low-grade appendiceal mucinous neoplasms, signet ring cell adenocarcinoma, and mucinous adenocarcinomas of the appendix, and mutations in the ARID2 gene in appendiceal goblet cell adenocarcinomas and appendiceal adenocarcinomas [11,184].